From Florida State's veteran line to Clemson's fearsome defensive front, the ACC projects to have some of the country's best position groups this fall, while a few other contenders will enter 2014 with some major question marks in key areas. With that in mind, we're looking at the ACC's best units, a few more that might surprise in 2014 and the top teams with holes that could keep them from an ACC title.

Up next: Defensive line.

Best of the best: Clemson

The Tigers are stacked on the defensive line, returning all four starters plus their top four backups from a season ago. Easy to see why Clemson gets the nod over the Seminoles -- sheer experience alone. Clemson has the best returning lineman in the league -- and one of the best in the nation -- in Vic Beasley, who had 13 sacks and 23 tackles for loss a year ago. His backup, Shaq Lawson, had 10 tackles for loss. That is more than anybody Florida State returns. So not only does Clemson have a group that is active behind the line, it has good depth, too, which should keep everybody fresh and make for one of the best line rotations in the country. If this group can live up to expectations, the Tigers have a chance to be one of the best groups in the entire country.

Next up: Florida State

If there is one constant in the ACC, it is a rock solid, dominant defensive line at Florida State. Five defensive linemen have been drafted over the past two years and another, Mario Edwards Jr., is rated as a top 5 defensive end among all underclassmen. There is no doubt the Seminoles are talented once again, but they do need to rebuild some depth across the entire line and may even rely on more linebackers to help out with the pass rush in 2014. Freshmen also will factor into the mix, as the Seminoles signed seven defensive linemen to help make up for some of the losses. Players such as Edwards, Eddie Goldman and Chris Casher are set to be the standouts on this group, but the Noles will need some unproven players to step up to keep the championship-level quality of the defensive line going.

Possible sleeper: Virginia

The Hoos have to replace two starters, but there is growing expectation for the line to be improved over a year ago. Eli Harold returns at defensive end after racking up 8.5 sacks and 15 tackles for loss a year ago, and has received early consideration as a potential All-ACC candidate. Mike Moore, slated to start at the other end position, was one of the defense's most improved players during the spring. Then, of course, there is incoming true freshman Andrew Brown, one of the top-rated players in the class of 2014 with an opportunity to make an immediate impact at tackle. Brown enrolled early and participated in spring practice. Though he battled through a bit of an injury, he is still in the mix to win a starting job.

Problem for a contender: North Carolina.

The Tar Heels have to rebuild along the front again, after losing starters Kareem Martin and Tim Jackson. Martin leaves behind the gaping hole, after racking up 11.5 sacks and 21.5 tackles for loss, along with 14 hurries a year ago. Even with Martin getting into the backfield, North Carolina ranked last in rushing defense, so there is no doubt this group has to make major improvements up front. Among the ends, only Junior Gnonkonde returns as a consistent contributor, with Jessie Rogers and redshirt freshman Dajaun Drennon in the mix. There is more depth at tackle than at end, though, so North Carolina will no doubt be growing up its ends in a hurry to make up for Martin's departure.